Absolute permissive block-signal system.



S. N. WIGHT.

ABSOLUTE PEHMISSIVFBLOCK SIGNAL SYSTEM. APPLICATION FILED MAR. 13. I913 RENEWED MAY 28. I913.

1,294,736. Patented Feb. l8, 1919.

4 S TS-SHEET I.

WITNESSES [N I E N TOR.

S. N. WIGHT.

ABSOLUTE PEHMISSIVE BLOCK SIGNAL SYSTEM.

APPLICATION FILED MAR. 13.19x3. RENEWED MAY 28,1918.

1,294,736. V Patented Feb. 18, 1919.

4 SHEETS SHEET 2.

FIG. 2.

WITNESSES: [NI EN TOR.

S. N. WIGHT. ABSOLUTE PERMISSIVE BLUCK SJGNAL SYSTEM. APPmmma mw MAR, 13 19:3 RENEWED MAY 28.1918.

1,294,736. Patented Feb. 18,1919.

4 SHEETS-8912f 3 m 4 ymf mlwiz S. N. WIGHT.

ABSOLUTE PERMISSIVE BLOCK SIGNAL SYSTEM. APPLICATION FILED MAR. 13.1913. RENEWED MAY 28. 1918.

1,294,736. Patented Feb. 18, 1919.

4 SH TS-SHEET 4.

WITNESSES. INVEN TOR.

. A T TQRNE UNITED STA ES PATENT OFFICE.

SEDGWIGK N. WIGHT, OF GATES, NEW YORK, ASSIGNOR TO GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEw YORK, .a CORPORATION OF NEW YORK.

ABSOLUTE PERMISS IVE BLOCK-SIGNAL SYSTEM.

Specification of Letters Patent.

Patented Feb. 18, 1919.

Application flledllarch 18, 1913, Serial No. 753,892. Renewed May 28, 1918. Serial No. 237,118.

Tooll whom it may concern.-

Be it known that I, Snoewxort N. WIGHT, a citizen of the United States, and a resident of the town of Gates, in the county of Monroe and State of New York, have invented a new and useful Absolute Permissive Block-Signal System, of which the following is a specification. v nThe obj ects of the present invention are to provide a'system of electric signaling for single track railways by which: st, a train whlch enters upon and moves in a certain direction upon a piece of single track between two passing sidings will prevent the entrance of a tram moving in an opposite direction upon the same piece of single track; second, with the same number of signals between sidings as are used in the best approved single track signaling of the present day, there may exist a very much less spacing distance for trains runnin under caution signals and much lessspacmg distance for trains running under proceed signals; third, no head-on flagging, with the consequent delay, will be needed; fourth, a much reater reliability of the distant signal in ication will be'obtained than is now obtained in the best approved single track signaling system heretofore known; fifth, equal or greater facility fortrain movements than is possible by means of the best approved single track signaling systems heretofore known; sixth, the results to be accomplished by nieans of apparatus constructed on exactly the same principles as is the apparatus now being used in the best approvedsingle track signaling system.

Other objects and advantages will appear as the description of the lnvention progresses, and the novel features of the invention will be particularly pointed out in the appended claims.

The system herein shown and described is one made possible by the invention of Wilmer W. Salmon and Frank L. Dodgson,

known as the Absolute permissive block signal system, disclosed in Reissue Patent No. 14,326. One great merit of the Salmon and Dodgson invention lies in the fact that twmsignaling circuits may be employed, one, opened by the presence of a train on any part of a certain track circuit section, the other, closed only by the entrance of a train from a predetermined direction upon the known, thoroughly tested and approved ap paratus such as is now universally used in railway automatic block signaling.

In describing the invention, in detail, reference is had to the accompanying drawing, wherein I have illustrated a preferred physical embodiment of my invention, and wherein like characters of reference designate corresponding parts throughout the several views and in which:

Figure 1, is a schematic view of a section of track, signals for controlling the movement of trains over the track, and the necessary apparatus and electricalcircuits needed to accomplish the objects of applicants invention; Fig. 2, is a schematic View similar to Fig. 1 and is a continuation thereof; Fig. 3, is a schematic viewsimilar to Fig. l and is a continuation of Fi 2; Fig. 4, is a schematic view similar to ig. 1, and is a continuation of Fig. 3. a

The drawin when placed in proper order end to en represent a continuous line of single track composed of rails 17 and 18, having two through passing sidings A and B connected thereto, arranged parallel thereto and connected in the usual manner to the line of single track by. switches 19, 19", 19 and.19

The section of track between the left hand end of Fig; 1 and the left hand and of gassing siding A, has been designated by' The sectlon of track coextensive with.

the passing siding A, has been designated The section of track from the right hand end of passing siding A to the left hand end of passing siding B, has been designated D. The section oftrack coextensive with passing siding B,.hasbeen designated B and B The section of trackway from the right hand end of passing siding B to the right hand end of Fig. 4, has been designated E. I

The amountof trackway taken for illustration land the number of signals shown, is such that two complete single track blocks have been illustrated; namely, D, and C and E, which together are of such length that they are equal to the length of section D. The illustration thus allows one to consider section C as a-continuation of section E, or, vice versa, that section E is the beginning of section C, so that as the description progresses and it is assumed that a train moving toward the right passes upon section C it may be considered that the train has just left section E and when it is later assumed that a train moving toward the right passes off from section E, that it then passes upon section C.

' The trackway, within the sections, is 'further divided by insulating joints 20 into separate, cl0sed circuited track circuit sections, each containing a batter 21 connect ed across the rails at one en of the section and relays as 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35 and 36 connected across the rails at the opposite end of the section. The operation of the track relays 22 to 36 inclusive, by the passage of a train, onto and over a closed track circuit section is identical with the known operation of such track relays as extensively used, and therefore does not merit further discussion or explanation. 1

The movement of trains over the track way in an easterly direction or toward the right of the figures, is governed by signals 1 to 8 inclusive. The movement of trains orer the trackway in a westerly direction or toward the left of the figures, is governed by signals 9 to 16 inclusive.

Signals 1 to 16 inclusive may be of any. of the well known and approved types as used either in single track signaling or double track signaling at the present day, that is, they should consist fundamentally of an operating motor of any of the well known types such as compressed air, carbonic acid gas, or electricity for moving the semaphore arm from its biased position to an operated position, known ordinarily as the caution position. and to another operated position, known ordinarily as the proceed position, and should furthermore each contain means which become operative upon the proper placing of the semaphore in either of its operated positions to retain it in such position, together with typical circuit controllers operated in conjunctionwith the movement of the semaphore to control the various operatin and holding circuits.

A thongh applicant has chosen to herein show a three-position signal in this particular embodiment of his invention, it 18 to be understood that he does not intend to exclude the use of the well known equivalents of a three-position signal because itis well known and understood by those skilled in this art that the same operating wires used for controlling a three-position signal may, for instance, he used equally as well for controlling two, two-position semaphore arms placed upon the same pole, or on separate poles, and it is further well known and understood bythoseskilled in the signaling art that two, two-position semaphore arms as ordinarily used impart exactly the same signaling information as does one threeposition semaphore arm.

Each signal mechanism has one or more circuit controllers operated thereby. These circuit controllers have been represented schematically as conducting arms 37 38, 39, i0, 41, it; is, 44, 45, 46, 47, i8-A9, 50, 51, 52, 53, 54, 55 and 56. Ea h of the conducting circuit controller arms 37 to 56 inclusive is operated by that signal mechanism adjacent to which it is located upon the drawings and is assumed to be in the position shown on the drawings when the signal adjacent to which it is placed on the drawings, is in the position as shown upon the drawings, and is further considered to be moved from the illustrated position to the dotted line position, indicated, upon a movement of the signal to the caution position and the danger position respectively. Arcs of varying length are struck concentric with the are describing end of the conducting circuit controller arm and by their varying length indicate the extent of rotative movement of conducting circuit controller arms during which they are in contact' with metallic strips assumed to be located in a position identical with the small arcs shown.

Each signal 1 to 16 inclusive has associated therewith and located adjacent thereto and in ordinary practice supported by the same pole which supports the signals, what are known as control relays 57, 58, 59, 6O, 61,

62, 3, 64, 65, 66,. 67, 68, 69, 70, 71 and 72.

described and each of the stick relays 73 to 84 inclusive is operated and controlled in the manner of the well known stick relay.

Certain of the signals as 2, 14, 6 and 10 do not have a stick relay directly associated therewith, but have instead pole changing rela s as 85,86, 87 and 88.

A though applicant has herein designated certain relays as track relays, certain others as control relays, certain others as stick relays and certain others as neutral, relays. it

is not to be inferred from such distinctive designating terms that there is in reality any essential or fundamentaldiflerence in the relays so designated, becauseall of the relays are essentially of the well known and ordinary type used for signaling purposes and vary not because of difference of internal construction, but rather because of the uses to which they are put, with the exception, however, that the control relays 57 to int 72 inclusive are constructed exactly like the other relays enumerated but have in addition a polarized armature designated in the several relays by 89, 9,0, 91, 92, 93, 9 95, 96, 97 9s, 99, 100, 101, 102, 103 and 104., which is operated by the same operative coils as used in each of the relays to operate their armatures and which standsin a position represented by a vertical positionon, the drawings, when the current flowing through the coils, is in one directiombut which has its lower end moved to the left upon a flow of current through the coils of the relay in an opposite directio Each of the signals directly movements of trains onto or over track sections C, D and E, have connected therewith a pole changing switch of the ordinary form which has been illustrated on the drawings in the ordinary manner and designated by the numeral applied to the signal which governs it, with the addition ofja superior as 16 1 15 3 13 4 12 5 11 7 9 and 8 Each of the pole changing switches are operated by the mechanism which operates the semaphore of the signal to which it isattached and is in the position as shown upon the drawings when the signals are in the position as shown upon governing.

the drawings and remains in such position even after the respective signals move to the caution position, but upon a movement" of the signal controlling a pole changing switch to a position below the caution posi tion, then the switch is thrown instantly to the full extreme of its other position as shown in dotted lines upon the drawin and remains in such thrown position while the signal is in any position below the caution position. When the signalmoves from the-biased or danger position toward the caution position, each of the pole-changing switches remains in the dotted line position until the signal reaches the caution position in its upward movement, whereupon the pole-changing switch is instantly thrown to the position as shown in full lines upon the drawings and remains in such position during any further upward movement of the signal toward and in the proceed position.

At suitable positions along the single track which has been illustrated, suitable sources of current supply have been placed such as 105,106, 107, 108,369,109, 110, 111,.

112, 113, 114,115, 116, 117, 11s and 119. In the drawings the sources of current supply have been illustrated as batteries, but it is to be understood that such illustration by no means precludes the use of any suitable source of current supply, nor is it to be considered to preclude the use of other arrangements of current supply because it is well understood by those skilled in the signaling art that the electric current which must be supplied to a system as shown by applithe single cants drawings, nay be supplied not only by a single source located-as shown uponthe drawings, but by full equivalents there-- 1 schematically illustrated in the conventional ;mannerand that the relay armatures act as circuit controllers to close certain circuits when the relay is energized or to close cer- Y tain circuits when the relay is deenergized or both, as is well understood by those skilled-in this art. a y 1 In order to explain the operation of the system which applicant has illustrated, it will be supposed that a train easterly direction, that is, toward the right 1 enters upon track circuit sectiofi (3 If the train considered, so enters ,track circuit section C. it may be considered that it does. so by leaving track circuit section Esme as will be more fully understood ",after a complete reading of this 'description, but which will necessarily have to be assumed to be trueat'the present, the signal 16 would then be'in' the danger position,

but even if signal 16 was not then in danger position, it would be placed in the danger position by the entrance of the train to track circuit section 0 because the entrance of the train to track circuit section C would shunt the relay 22 and would thereby cause the control relay 57 to be deenergized, thus breaking the circuits controlling both the caution and the proceed aspects of signal 16. The details of the operation would be as follows: The train entering upon track circuit section C would cause armature 120 to fall thereby breaking the circuit which is shown existin between wire 121 and wire 122, and it, willfime further seen that wire 122 is the only means shown for-completing one side of the" circuit to control relay 5?, consequently, irrespective of what causes a flow of -current through 'control relay 57 the dropping of armature 120 would; cause the flow of current to cease through the control relay 57. The dcenergization of control relay 57 would causearmature 123 to fall, but would not afi'ect theposition of polarized armature89. Upon the dropping of armature 123, the only path by which signal 16 can derive current from-battery 105 would be broken, because the current flows from battery 105 to signal 16 in the following path: positive terminal of battery 105, wires 124. 125 and 126. armature 123 then to wire moving in an breaks the continuity of both of the circuits,

so that current cannot flow through the proceed control wire 129 or the caution control wire 211, consequently the sums the full bias or danger position. The condition of the several arts heretofore described as being operated: will remain in the positions as just described just so long as the train remains upon the rails of track CiI'CUibSeCtlOn C The entrance of the train in its forward movement ontothe rails of track circuit section C will in a similar manner cause a deenerg'ization of trackrclay 23, a dropping of armature 133, a consequent decnergization of controhr'elay 58 and a dropping of armature 134, which controls the caution and proceed positions of signal 1 just as relay armature 123 controls the caution and proceed positions of signal 16. The entrance of a train upon track circuit section C moving in the direction'assumed, operation which it didnot cause when it entered track circuit section C. This further operation is a preliminary and maintained energization ofstick relay 7%, The

preliminary and maintained energization of 7 stick relay 7 1. depends in the physical embodiment of applicants invention shown, primarily upon the fact that at the time-the train considered, entered track circuit section C the signal 1 was in the proceed position and consequently, conducting circuit controller arm 38 was in the position as shown in the drawing, making electrical contaot with the are shaped metallic strip 135. Upon the entrance of the train upon track circuit section C as has heretofore been pointed out, the track relay 23 was shunted and not only armature 133, but armature 136 dropped, so that a circuit was formed in which current flowed as follows: positive 'terminal'of battery 106, wires 141 and 137, conducting circuit controller arm 38, metallic strip 135, wire 138, armature 136, wires 139 and 149, stick relay 7 1, wires 140, 112, and 1 13, ,to the negative terminal ot the battery 106. The flowof current in the just above traced path causes an energization of relay 74' and thereby causes armature 1 14 to be raised to its upper position. It should be noticed that current in the circuit just above-traced would only flow momentarily because upon the dropping of armature 13-1 the circuit of both of the control wires for signal 1 would be broken, consequently, the

signal will ascauses a further danger position would break contact with metallic strip 135 thereby breaking the above traced circult, but, the above traced circuit would not be broken however, until armature 144 had been raised because armature 136 is much quicker in its movement than therarm of signal 1, due to the intertia of the parts of the mechanism connected with signal 1.

A train occupying track circuit section C causes a deenergization of control relay 58 and a consequent dropping of armature 134, and the armature 144 being now in the raised position a circuit would be completed in which current flows as follows: positive terminal of battery 106, wires 141,145 and 146, armature 13%, wire 147, armature 144, wires 148 and 1-19, stick relay 74, wires 1-10, 142

sition of conducting circuit controller arm 38 and furthermore, that it will remain completed just so'long as the train considered remains upon the rails of track circuit section 0 because just so long as a train remains upon the rails of track' circuitsection C the control relay 58 will be dencrgized and armature 134 will be in its lower position making contact with wire 1-17.

The energization of relay 7); causes armature 150 to be raised and remembering that the movement of the signal 1 to the full dan ger position causes pole changing switch 1 to move to the dotted line position, will complete a circuit in which current flows as follows: positive terminal of battery 106, wires 141, 145 and 151, pole changing switch arm 152, in the dotted line position,-wires-153, 151, 155, 156 and 157 to wire 158, as it has heretofore been pointed out that section E may be considered as the beginning of section C, then by wires 159 and 160, control relay 72, wire 161, armature 162, wire 163 to wire 164, as itvhas heretofore been pointed out that section C may be considered as the continuation of section E, then by means of armature'165, which is in the upper position, as soon as all of the train which has been considered gets upon the track circuit section 0 then by wire 166 to armature 167, which is in the lower position as shown because stick relay 73 as heretofore stated was not preliminarily energized and maintained energized by the entrance of a train upon track circuit section C the reason for which will appear later, but at present it must suflice to say that a stick relay which is preliminarily energized by acircuit completed through a ments in a direction opposite to the move- 169 to armature 150, which in the manner heretofore pointed out and explained, was

raised to the upper position and maintained in the upper position similarly to armature 144, so that the current flow continues to wires 170, 171, and 172 to arm 173 of' the pole changing switch 1 which is in the dotted line position as the signal 1 is in the danger position, th'ence by wires 174 and 143 to the negative terminal of the battery 106. The result of the flow of current last described is to energize control relay 72 thereby causing armature 17 5 to be raised to the upper'position as shown, consequently, allowing current to flow from the positive terminal of the battery 119 by wires 176, 177 and 178 and armature 175 to wire 179 and by one of the multiple paths from wire 179 to wire 180 to and through the signal mechanism of signal 8, and by means of wires 181, 182 and 183, to the negative terminal of the battery 119. The current flowing in the last traced path causes the signal arm8 to move to the caution position, but it will not be moved to the proceed position because current cannot flow from wire 179 through wire 184 and through armature 104 to wire 1'85 and thence to the signal mechanism, because the path for current which was formed by the raising of armature 150 allowed currentto flow from battery 106 through pole changing switch 1 in such a direction that control relay 72 was so energized that it caused armature 104 to break contact with wire 185. Thus it will be seen by placing the left hand end of Fig. 1 in a position which makes it a continuation of the right hand end of Fig. 4, that a train moving in an eastcrly direction upon the track circuit section C would have a danger aspect exhibited by signal 1 behind it and a caution aspect exhibited by signal 8 behind it one block in the rear, and that such condition would continue to exist just so long as any part of the train occupied the rails forming part of track circuit section C and also just so long as a train occupied the rails of track circuit section O because the entrance to and presence of a train upon the track circuit section C would cause a denergization of track relay 24 thereby allowing armature 186 to move to the. lower position breaking contact with wire 187, so that although the passage of the train entirely off from the rails of track :cir'

cuit section C would allow relay 23 to be energized and cause armature 133 be raised thereby completing the break that'iwas made in the circuit for c ntrol relay 58,

nevertheless the circuit for control relay 58 would be broken between armature 186 and wire 187 so that armature 134 would continue in its lower position maintaining the energization of stick relay 74 and causing armature 150 to remain in the upper position making contact with wire 170.

As soon as the train, which I have assumed to be moving easterly upon the trackwav has passed upon the section A control relay 58 will be energized by a current which flows from battery 108 through the armatures 188 and 189 in their lower position be cause they will be in their lower osition for reasons to be later explained. i he circuit in which current flows, including control relay 58, will therefore be as follows: positive terminal of battery 108, wires 190 and 191, armature 188, wires 192, 193,194, 195, 196, 225, 154 and 197, control relay 58, wire 198, armature 133, wire 199, armature.,-186, wires 187 and 200, armature 189 and wires 201 and 202 tothe negative terminal of the bat tery 108. The flow of current in the path last described causes armature 184 to be raised, thereby breaking the circuit for maintaining the energization of stick relay 74 and allowing its armatures to fall and also allowing current to flow from the positive terminal of battery 106 through wires 141, 145 and 146 and armature 134 to wire 203 and thence by the caution control wire 204 to the signal 1, returning by wires 205, 142 and 143 to the negative terminal of the battery 106. Current would not flow, however, from wire 203 to wire 206 and through armature 90 to proceed control wire 207 to the signal 1, because the flowof current from the battery 108 through the coil of control relay 58 causes'suchan energization of the poles of control relay 58 that the armature 90 is movedgto the left away from contact with wire 207, consequently, the train standing upon track eircuitsection A would be protected by a signal 2 at danger directly behind it for reasons to be later explained and by a caution signal 1, one block in the rear.

the manner heretofore explained and the movement of the signal 1 to the caution, pr

sition causes armaturef208 to be moved to the upper position and also causes pole changing switch 1 to be thrown from the dotted line position to the full line position, so that the current which flowed as herein before explained from the positive terminal of battery 106 by means of wires 141, 145

and 151 and pole changing switch arm 152,

to wire 153 and thence by wires 154, 155, 156,157,158, 159 and 160 to control relay 72 would now flow from the positive terminal of battery 106 to wires 141, 145, and 151 to pole changing switch am 152, thenceby wires 171 and 209 to armature 208and then through wires 164 and 163 to armature 162 and then by means of wire 161,.to control relay 72. It will thus be seen that the po-.

larity ofYthe currentthen flowing through the control relay 72 would be exactly the .op

. posits to that which flowed when the pole changing switch 1 was in the dotted line position and the armature 150 was in the raised osi-tion, and as the current which former y flowed caused armature 104 to be moved to the left, the current which now flows will cause armature 104 to be moved to the right makingcontact with wire 185. The current which now flows and whichhas' heretofore been traced as flowing through control relay 72 by means of wire 161,wou 'd, flow back to the negative terminal of the battery 106- in the followin path: wires 160, 159, 158, 157, 156, 1-55, 15 and 153 t5 pole changing switch arm 173, thence -b 5 wires 174 and 143 to the negative termina of the battery.

The movement of polarized armature 104 to the right while armature 175 is in the raised position, would allowcurrent to flow from battery 119 to the proceed control wire and flow as follows: positive terminal of i the battery 119, wires 176, 177 and 178, ar-

mature 17 5, wires 179 and 184, polarized armature 104, and proceed control wire 185 to the signal 8 thence returning by wires 181, 182 and 183 to the negative terminal of the battery 119, thus causing the-signal 8 a to be moved to the full proceed position, so 7 that then the'train standing on track Section A would have a full danger signal protecting it directly back of it, a caution sigmil 1, one block in the rear, and a full proceed signal.8 two blocks in the rear.

upon track circuit section C would den- 1 ergize relay 22 which, as hereinbefore explained, would deenergizecontrol relay 57 if it were not already deenergized, thereby allowing armature 220 to drop which would cause a deenergization of control relay 59, because relay 59 has current flowing through it when energized in a circuit as follows: positive termlnal of battery 105, wires 124, 125 and 221, arm 222 of pole changing switch 16 in the dotted line position. if slgnal 16 is in the danger position and wires 224,155, 154, 225 and 226 to control relay 59, then "by wire 213, armature 212, wire 348, armature 219, wire 227, armature 228,

wires 229, and 230, armature 220, wires 231, 232, and 265, arm 223 of pole changing switch 16 and thence by wires 233 and 132 to the negative terminal of battery 105.

The circuit above traced as hcrctoforem pointed out would be broken by the dropping of armature 220 upon the entrance of a train totrack section C if it were not already broken because of the fact that the armature 220 was then already in the lower position, and the armature 220 would remain in the lower position just so long as the train was upon track circuit section C because 5f the continued dcenergization of track relay 22 and the consequent deie'nergization of control relay 57.

When the train considered moved from track circuit section C to track circuit section C it would allow track relay 22 to be again-energized, but it would at the same time, however, dcilnergizc relay 23 and sub sequently relay 24 upon entering track circuit section C and so cause armature 219 59 would remain in the lower position to which it had been allowed to move, if it were not already in that position, by the dcenergization 0 control relay 57, thereby continuing the disconnection of wire 215,

which feeds current to both proceed control 7 Wire and the caution control wire of signal 15, from its previously formed connection 'by means of wires 216, 217 and 218, with the positive terminal of the battery 107. thus causing the signal 15 to remain in the full biased or danger position, if it is already there, or allow it to move to such position.

it it is not already there.

I Will now return to consideration of thc operation which takes place upon the ontrance of the train to track circuit section A.

Upon the entrance of a train onto track circuit section A the relay is dci ncrgized, thereby allowing armature 234 to drop, thus breaking connection between armature 234 and wire 235, so that control relay 60 is dccnergized. The normal circuit for control relay 60, in which current flows, is as follows: positive terminal of the battery 109, wires 236, 237 and 238, arm of pole changing switch 3 in the full line position, wires 240, 241, 242 and 243, armature 244, wins 245 and 235. armature 234, wires 246 and 247, control relay 60, wires 248, 219, 101, 250. 251, 252, 253 and 251, arm 255 of pole changing switch 3 and wires 256 and 257 to the negative terminal of battery 1.99. The breaking of thc abovo traced path causcs a cessation of the flow of current through the control relay 60, thus .Egle changing allowing the armature 258 to drop to the lower position, so that the current which previously flowed from battery 108 by means of wires 190 and 259, through armature 258 to wire 260, and thence to both the proceed control wire and the caution control wire of signal 2, is interrupted, and signal 2 moves to the full danger or bias position.

The movement of signal 2, to the danger position causes circuit controller arm 41 to break contact with wire 261, consequently relay 85, which I will designate as a pole changing relay becomesdeenergized, because the circuit controller arm 41 is an integral part of the circuit controlling pole changing relay 85 and normally current flows to energize the'pole changing relay 85 in the following circuit: positive terminal of battery 109, Wires 236, 237 and 238, arm 239, of pole changing switch 3 in the full line position, wires 240, 241, 242 and 262, armature 263, wires 264, 334, and 261, metallic arc 333, arm 41, then by wire 266 to pole changing relay 85, and thence by wires 267, 249, 194, 250, 251, 252, 253 and 254 to arm 255 of pole changing switch 3, and thence by wires 2,56 and 257 to the negative terminal of the battery 109.

It is to be noted that battery 109 furnishes energy for both control relay 60 and relay 85, and that between the tteries an the relays a pole changing switch is interposed, but the pole changing switch and the polarit of the current flow has no effect upon p0 e changing relay 85 because a current flowing through pole changin relay 85 in either direction causes it to hold the neutral armatures 188 and 189 in the upper position and if the current ceases the armatures fall to the lower position. The polarity of the current flowing through the control relay 60, however, de-

termines the aspect of signal 2 because the normal flow of current from battery 109 to control relay 60 is in such a direction that armature 92 is moved to the right into contact with the proceed control wire 268, but when the current from the battery 109 through the control re ay' 60 is in the reverse direction the polariz armature 92 is moved to the left out of contact with proceed control wire 268, thereby causing the arm 2 to move to the caution position from the proceed position, if armature 258 is at that time in the upper position but if the current ceases entirely as by the presence of a train upon track circuit section A causing a denergization of relay 25, and allowing armature 234 to fall, then current from battery 108 could also be cut off from caution control wire 269 and the signal 2 will move to the full danger or bias position.

The train upon track circuit section A would then be protected by a full danger signal 2 directly behind. it, and acaution sig- 'rela 58 would be energized by the passage of t e train off from track circuit section C the circuit heretofore traced for control relay 7 2, would be completed through the pole changing switch 1 in the full line position, so that current would flow through the battery 106, through the control relay 72 in the normal direction, so that polarized armature 104 would be moved to the right thereby completing the circuit from battery 119 to both the caution control wire 180 and the proceed control wire 185 of signal 8, so that there would also be a proceed signal two blocks in the rear of the train.

The train which has hereinbefore been assumed to be upon the trackway illustrated by the drawings, is now positioned on the track circuit section A directly in the rear of the insulating joints opposite signal 3. It will be assumed that no train is upon any part of the single track block D and that, therefore, signals 3, 4, 5, 6, 11, 12, are all in the normal position as shown so that the train by reason of the proceed position of signal 3 has full rights to enter the single 7 track block D at full speed.

The pro ress of the train through the single track b ock D will now be described; having reference merely to those signals upon the track circuit section D the tra :k relay 26 is denergized thus allowing arm: sure 270 to fall and as the circuit for contibl relay i 62 is formed through armature 270, in its upper position through wire 288, then control relay 62 will be denergized and allow Varmature 271 to fall to its lower position, thus interrupting the flow of current from battery 109, through wires 236, 237 and 314, and armature 271 to wire 315and thence to cantion control wire 27 3 and proceed control wire 272 of signal 3. Signal 3 consequently moves to the full biased or danger position protecting the rear of the train.

The deenergization of relay 26 also allows armature 316 to fall, and as hereinbefore explained, as it moves uicker than the arm of the signal 3, it will c ose acontact connected with wire 317 before conducting circuit controller amn43 has moved out of contact with metallic are 318, so that a circuit will be formed through the stick relay 76, in which current flows, as follows: positive terminal 76 energized, even after conducting circuit controller arm 43 moves out of contact with metallic are 318, due to the movement of the signal" mechanism' and signal to the full biased or danger position, during all of the time that the train is upon track circuit secto close a circuit through control relay 60,

tion D and also while the train is upon track circuit sectionD", because the entrance of the train 'to track circuit section D causes a denergiza'tion of relay 27 thus allowing armature 274 to fall, and breaking the, circuit 'forco'ntrol relay 62, which is connected" to armature, 274,

through .wire 288, armature 270, and wire 2 9. y

The object of energizing stick relay; 7 6 is so that signal 2 may receive current from battery IOS through its caution control wire, so as to be thereby moved to the caution position. While the train was upontrack circuit section A, relay 25 was dener 'zed allowing armature 234 to fall, thus brea 'ng thecircuit through control relay v60, which is connected to armature 234, by. means of wires 247 and 246. When the train moved ofi' from track circuit section A and entirely upon track circuit section D relay 25 was again energized and armature 234 was raised, but at the same timearmature 244 controlled by relay 26, was allowed to fall to the lower 7 position, thus breaking the same circuit at another-point as the circuit for control relay 60 is controlled through armature 244 bv means of wires 245 and'235, armature 234, wires'246 and 247. When stick relay 76 is energized and armature 326 is raised, current can then flow through the control relay Bfljrom battery 109 in the following ircuitipositiveterminal of battery 109, wires 236, 237 and 238, arm 239 of pole changing switch 3 which is in the dotted line position, because signal 3 is in the danger position, wires 254, 253, 252, 251, 250,194, 249 and 248, to control relay 60, from control relay 60, through wires 247 and 246, armature 234, wires and 329, armaturef326,

wires 330, 240 and 331, arm 255 of ole changing switch 3 and wires 256 and 25 to the negative terminal of the battery'109. Current flowing in the above traced path energires control relay 60, causing armature 258 to be moved to theupper position, but, as pole changing switch 3 has been reversed, the direction of current flowing from battery 109 through control relay 60, is the reverse of normal, consequently, the armature 92 is movedto the left out of contact with proceed control wire 268. The raising of armature 258' allows current to flow from battery 108 to signal 2, in the following path: positive terminal of battery 108, wires 190 and 259, armature 258,'wires 260 and 269, signal mechanism 2, and wires 332 and 202 to the negative terminal of the battery 108. The current flowing in the above traced path causes the signal 2 to assume the caution aspect.

The presence of the train upon track circuit section A, caused the signal 2 to assume the danger aspect, thus interrupting the circuit at conducting controller arm 41 between wires 261 and 266, thus causing pole changer,

relay 85 to become denergized as the circuit for pole changer relay 85 is formed through the circuit controller arm 41, by means of.

wire 266. The passage of the train entirely onto track circuit section D cause as has hereinbefore pointed out, a movement of signal,2 to the caution position, thus allowing conducting controller arm 41 to again make contact with metallic strip 333, and

thus complete the circuit from wire 261 to wire 266, but the movement of the same into the track circuit section D deiinergized control relay 62 and caused armature 263 to fall so that the circuit of pole changer relay 85,.is broken at another point. The energization of stick relay 76, however, forms a circuit in which current can flow to the pole chan ing relay 85 as follows: positive termina of battery 109, wires 236, 237 and 238, arm 239 in the dotted line position, wires 254, 253, 252, 251, 250, 194, 249 and 267 to pole changing relay 85 and from the pole changing relay by wire 266, conducting controller arm 41, metallic are 333, wires 261, 334, 335 and 336, armature 325, wires 337, 241, 240 and 331, controller arm 255 of pole changing switch 3 in the dotted line position, and wires 256 and 257. to the negative terminal of the battery 109. i

The energization of pole changing relay 85 in the manner just described causes the armatures 188 and 189 to be raised, thereby restoring all parts of the mechanism connected with single track section C to the normal o sition as shown.

The progress of the train through track circuit section D does not alter any of the conditions which have heretofore been established but upon the entrance of the train The entrance of the" train to track circuit section D in a manner identical to that described in connection with signal 3, causes a preliminary and maintained energization of stick relay 78, so that control relay 62 which was deenergized by reason of the armature 274 being in its lower position, would still be denergized by reason of armature 303 being in its lower position as the normal circuit for control relay 62 is as follows: o'sitive terminal of battery 111, wires 278, 27 9 and 280, arm 281 of pole changing switch 4 in the full line position, Wires 297, 296 and 302, armature 303,- wires 304 and 292,'armature 291, wire 290, armature 274, wire 289, armature 270, wire 288, control relay 62, wires 287, 253, 286, 285, 284, 283 and 282, arm 299 of pole changing switch 4 in the full line position, and wires 300 and 301 to the negative terminal of the battery 111, but although armature 303 is in its lower position a circuit will be formed through control relay 62 in which current flows as follows: positive terminal of battery, 111, wires 278, 279 and 280, arm 281 in the dotted line position due to the position of the pole changing switch 4 by the movement of the signal 4 to the danger position, wires 282, 283, 284, 285, 286, 253 and 287, control relay 62, wire 288, armature 270, wire 289, armature 274, wire 290, armature 291, wires 292 and 293, armature 294, wires 295, 296, 297 and 298, arm 299', in the dotted line position and wires 300 and 301 to the negative terminal of the battery 111. The current flowing in the above traced path would energize the control relay 62, but as the current flows in a direction opposite to the normal flow, polarized armature 94 would be moved to the left, thereby breaking contact with the proceed control wire 272 of signal 3, but as armature 271 would be thereby raised, cur rent would flow in a path heretofore traced from battery 109, through the caution con, trol wire 273, to signal 3, returning in the usual manner so that the signal 3 would assume the caution aspect. The train upon track section D would thus be protected by a full danger signal directly behind it and a caution signal one block in the rear, which condition would be also maintained during its passage onto and through section D because its presence upon track circuit section D would cause a deiinergization of track relay 29 and thus allow armature 305 to fall, which would act in the same manner as armature 275 to break the circuit of control relay 64.

When the train passed from the section D to track circuit section D control relay 62 became energized, therefore armatures 263 and 271 were raised thus breaking the circuit for stick relay 76 and so causing armatures 324, 325 and 326 to fall, and also causing signal 3 to move to the caution position, thus shifting pole changer switch 3 from the dotted line position to the full line position, so that current then flowed from battery 109 to control relay 60 in the normal direction as follows: positive terminal of battery 109, Wires 236, 237 and 238, arm 239 of pole changing switch 3 in the fullline position, wires 240, 241, 242 and 243, armature 244, wires 245 and 235, armature 234, wires 246 and 247, control relay 60, wires 248, 249, 194, 250, 251, 252, 253 and 254, arm 255 of pole changing swltch 3 in the full line position and wires 256 and 257 to the negative terminal of the battery 109. As the current then flows through the control relay 60 in the normal direction, the polarized armature 92 will be moved to the right thereby making contact with proceed control Wire 268 so that current may flow from battery 108 in the path he etofore traced to and through the proceed control wire 268 and the signal 2, returning in the usual path. The train while situated upon either track circuit section D or D will therefore have a full danger signal 4 directly behind it, a caution signal 3 one block in the rear, and a proceed signal 2, two blocks in the rear. 1

When the train moves upon track circuit section D, track relay 30 is deenergized and mature 306 isallowed to fall thereby breaking the circuit for control relay 66, and allowing armatures 311 and 307 to fall, so that in the same manner as heretofore described in connection with signals 3 and 4, the signal 5 will move to the full biased or danger position and stick relay 80 will be energlzed and maintained energized, so that the operation will be identical with that which took lace when the train passed from track circuit section D to track circuit section D that is, the circuit for control relay 64, which normally passes through armature 311, will be broken at that point, but another circuit in which current flows in a direction reverse to normal will be formed from batter 113 through the pole changing switch 5 1n the dotted line position due to the danger position of si al 5 and through armature 309 in the raised position. This current will act upon control relay 64 just as the current which has hereinbefore been described flowing from battery 111 acted upon control relay 62, so that polarized armature 96 will be moved to the left breaking contact with the proceed control wire 339 and armature 276 will be moved to the upper position allowing current to flow from battery 111 to and through the caution control wire 338, to cause the signal 4 to assume the caution aspect. At the same time stick rela 78 will become deenergized by reason 0 the raising of armature 276, and the current flowing from battery 111 to control relay 62, would flow in its normal path through armature 303, controlled by control relay 64, and as signal 4 would be moved to the caution position pole changing'switch 4 would be moved to the full line position so that the current flowing in its normal direction from battery 111, would flow in the following path: positive terminal of battery 111, wires 278, 279 and 280, arm 281 of pole changing switch 4 in the full line position, wires 297, 296 and 302, armature 303, wires 304 and 292, armature 291, wire 290, armature 274, wire 289, armature 270, wire 288, control relay 62, wires 287, 253, 286, 285, 284, 283 and 282, arm 299 of pole changing switch 4 in the full line position and wires 300 and 301 to the negative terminal of battery 111. As the current flows from battery 111 to control relay 62 in the normal direction the armature 94 will be moved to the right making contact with proceed control wire 272 of signal 3, consequently, signal 3 will be moved to the proceed position.

During the time that the train is upon track circuit section D the conditions will be maintained as already described. The movement of the train upon track circuit section D will not alter any of the essential conditions, the only change being that the circuit of control relay 66 instead of being broken at armature 306 will be broken at armature 310, which will be allowed to fall .by thedeenergization of track relay 31.

.The movement of the train onto track circuit section B would have exactly the same efi'ect that the movement of the train upon the track circuit section A had, as hereinbefore described, that is, control relay 68, would be deenergized, thus allowing arniature 340 to fall, thereby interrupting both theicaution and proceed control wires governing signal 6, which, consequently, moves to the full biased or danger position. and by so doing, causes conducting controller arm 51 to move from in contact with metallic strip 341, thus breaking the circuit of pole changing relay 87, and allowing armatures 342 and 343 to move to the lower position, and as armatures 306 and 310 would be in the u per position after the train leaves sectlon l), a current would flow from battery 115 to control relay 66, in a direction reverse to normal so that polarized armature 98 would be moved to the left breaking contact with proceed control wire 344and armature 307 would be raised making contact with caution control wire 345, so that signal 5 would be moved to the caution position, just as has been, described hereinbefore in connection with signal 1.

The energization of control relay 66 would cause a deenergization of stick relay 80, consequently, armature 309 would be allowed to fall and, the current from battery 113 would flow in its normal direction throu h armature 311 to control relay 64, there y .upon the movement of the train onto track circuit section B except that the circuit for control relay 68 would be broken at armature 346 by the deenergization of track relay 33 instead of by the armature 347.

The further movement of the train on the system would merely result in arepetition of those operations which have already been described in connection with signals 1, 2,3 and 4, and therefore does not need further I description.

The circuits and controlling apparatus and signals governing the movements of a train for one direction only having been described in connection with single track block D, it now remains to describe the means for obtaining head-on protection, that is, the means for preventing a train from entering the single track block D while the train which has hereinbefore been considered, is progressing through the single track block D.

As soon as the train which has hereinbefore been considered, entered upon track circuit section D from track circuit section A, it was necessary that signals such as 11, 1'2, 13 and 14, governing train movements in a westerly direction over single track block D, should be placed in a danger position. The entrance of a train from track circuit section A to track circuit section D deenergized track relay 26, which allowed armature 350 to fall to the lower position, thereby breaking the circuit olu-ontrol relay 63 of signal 13, this circuit being identical in all respects with the circuit of the control relay of signal 1. The deiinergization of control relay 63 allows armature 351 to fall, thereby interrupting the current from battery 110 to the caution control wire 352 and the proceed control wire 353, of signal 13, consequently the signal moves to the full biased or danger position. At the same time the falling of armature 354 by reason of the .denergization of control relay 63, breaks the circuit through control relay 65, the circuit of which is identical with that of signal 8, hereinbefore described. The deenergization of control relay allows armature 355 to fall thereby causing an interruption of the current from battery 112 to the caution control wire 356 and the proceed control wire 357 of signal 12 so that signal 12 will move to the danger position. The falling of armature 358, allowed by the denerglzation of control relay 65, interrupts the circuit for control rela 67, the circuit of which is identical with that of the control relay of signal 3, hereinbefore described. The deenergization of control relay 67 allows armature 359 to fall, thereby interrupting the flow of current from battery 114 to the caution control wire 360, and the proceed control wire 361 of signal 11, thus allowing the signal 11 to assume the full danger or biased position.

It is thus seen that the entrance of a train moving in an easterly direction onto the track circuit section D will instantly cause all of the signals governing movements in a westerly direction over the single track block D, to move to the full biased or dan er position so that the east bound train is fudly protected from any opposing train move-- ment.

While the east bound train is upon the track circuit section D, the condition of signals 11 to 13 inclusive would remain as.

described and due to the reasons given. When the train is upon track circuit section D the circuit for control relay 63 is broken at'armature 362, so that the signals 11, 12 and 13 remain in the danger position. When the train enters upon the section D, the circuit for control relay 65 would be broken at armature 363 and also at armature 364, due to the energization of stick relay 78, this latter break in the circuit being made simply as an additional precaution to insure the deenergization of control relay 65. When the train moves upon track circuit section D, the circuit for control relay 65 would be broken at armature 365 and at armature 364. When the train moves upon track circuit section D", the circuit for control relay 67 would be broken at armature 366, and at armature 367, of stick relay 80. When the train enters upon track circuit section D", the circuit for control relay 67 would be broken at armature 368 and armature 367. The movement of the train from track circuit section D to track circuit section B would result in signals 11, 12 and 13 all being left in the full clear position, because when the train which has hereinbefore been considered passed signal 13, and was entirely upon track circuit section D, the control relay 63 of signal 13 immediately became energized as there was no train upon section D so armature 362 was moved to the upper position and as there was no train upon track circuit section D. the armature 350 was raised to the upper position so that a circuit from battery 369 was formed to control relay 63, identical.

with a circuit heretofore described controlling control relay 58 of signal 1, so that signal 13 would assume the full clear position.

The passage of the train from track circuit section D* to D would allow track relay 29 to become energized, thereby raising armature 365 to the u per position and at the same time track rel ay 28 would be energized thereby raising armature 363 to the upper position, and at the same time armature 364 would be in the lower osition due to the passage of the train ofi rom track circuit section D*, resulting in a deenergization of stick relay 78, and at the same time as here inbefore explained control relay 63 would be energized thereby causing armature 354 to be in the upper position, consequently, current from battery 110 would flow through and energize control relay 65 by a circuit identical with that hereinbefore described in connection with the control relay 64. The movement of the train from track circuit section D to track circuit section B would allow relay 31 to become energized thereby raising armature 368 to the upper position and at the same time armature 366 would be in its upper position due to a previous energization of track relay 30 and armature 367 would be in the lower position due to the deiinergization of stick relay 80, by the movement of the train from track circuit section D to track circuit section B, and armature 358 controlled by control relay 65 would be in the upper position due to th energization-of control relay 65 in a manner hereinbefore described so that current would flow from battery 112 to energize control relay 67 and so place signal 11 In a proceed position by a circuit iden ical with that by which current normally ows from battery 111 to energize control relay 62, c-ontrollin signal 3.

The operation of the signal mechanism and controlling arrangements for signals governing following movements, and also for signals governing opposing movements has now been described with the exception that the action of signals such as 2, 14, 6 and 10, for opposing movements remains to be described.

The control relay for signal 10, s 69, and the circuit including the control relay 69 in which current normally flows is as follows: positive terminal of battery 114, wires 369, 370 and 371, arm 372 of pole changing switch 11 in the full line position, wires 373, 374, 375, 376 and 427, armature 377, wires 378 and 379, armature 380, wires 381 and 382, armature 383, wire 384, control relay 69, wires 385, 386, 387, 388, 389, 390 and 391, arm 392, of pole changing swltch 11 in the full line position, and wlres 393 and 394 to the negative terminal of the battery 114. The current flowin in the above traced path with the parts as s own in the drawing will be in such a direction through the control relay 69, that armature 101 will be moved toward the right into contact with proceed control wire 395, and consequentl the signal will be held in the procee position,

but, as soon as a train moving in an easterly direction, enters the track circuit section D then the signal 11 is allowed to fall to the danger position, thereby moving the pole changing switch 11 from the full line position to the dotted line position, so that current which normally flows from the positive terminal of battery 114, by means of wires 369, 370and 371, and arm 372 of pole changing switch 11 in the full line position, to wire 373, and thence through the wires and armature heretofore pointed out to wire 384, would instead flow from the positive terminal of the battery 114, through wires 369, 370, and 371, arm 372 of pole changing switch 11 in the dotted line position, and a thence by means of wire 391, 390, 389, 388,

387, 386 and 385, to the other side of the control relay 69, so that the current through the control relay 69 would be reversed in direction and the polarized armature 101 would be moved to the left breaking contact with proceed control wire 395 of signal 10 so that the signal would immediately assume the caution aspect, the moment a train entered from section A onto section D The signal 10 would remain in the caution position during the progress of the east bound train through the single track block D until such' train entered upon the rails of track circuit section D, whereupon by the denergization of track relay 31 and the consequent dropping of armature 377 the circuit for the control relay 69 would be broken and the armature 396 would be allowed to fall to its .lower position, thereby interrupting the flow of current from the battery 116 to the caution controlwire 397 of si a1 10 and causing said signal to go to 533 stop position. The movement of the train from track circuitsection D upon to track circuit section B, would break the same circuit at armature 380 controlled by track relay 32, and the movement of the train onto track circuit section B would break the same circuit at armature 383 controlled by track relay 33.

At the same time that signal 10 moves to the caution position, signal 9 also moves to the caution position, because the entrance of a train into track circuit section D from A will deenergize control relays 63, and 67 ashereinbefore pointed out and will cause signal 11 to move to the danger osition thereby causing conducting controler arm 49 to move out of contact with metallic are.

398 and will allow armature 399 to fall to its lower position, consequently, the circuit through pole changing relay 88 will be broken at armature 399. This circuit is normally as follows: positive terminal of battery 114, wires 369, 370 and 371, arm 372 of pole changin switch 11, in the full line position, wires 3773, 37 4, 375, 376 and 400, armature 399, wires 401, 402, 403 and 404, me tallic are 405, conducting circuit controller arm 52, wire 406, pole changing relay 88, wires 407, 386, 387, 388, 389, 390 and 391, arm 392 of pole changing relay 11 in the full line position, and wires 393 and 394 to the negative terminal of the battery 114. As soon as the train moves from track circuit section A to track circuit section B, the circuit heretofore traced through pole changing relay 88 would be broken at armature 399, and, consequently, armatures 408 and 409 would be allowed to fall to their lower 031- tion thus reversing the flow of current rom battery 116 to control relay 71, so that polarized armature 103 would be moved out of contact with proceed control wire 410 of signal 9, thereby interrupting the flow of current from battery 118 to the proceed control wire of-signal 9, thus allowing the signal to assume the caution aspect.

Signal 9 would remain in the caution position upon the passage of the train from track circuit section D onto track circuit section B, by reason of the fact that signal 10 having moved to the danger position when the train moved upon track circuit section D", thereby opening the circuit of pole changin relay 88 at the conducting circuit controller arm 52 and would also be maintained in such position after the train passed upon track circuit section B for the same reason.

It will be noted that signals 3, 7, 11 and 15 have two conducting circuit controller arms operated therewith, and that one of the conducting circuit controller arms associated with each of the said signals, to-wit, 44, 54, 49, and 39, are in a multiple circuit with the upper armatures of control relays 62, 70, 67 and 59 respectively. The result obtained by the use of the multiple connection shown can be best made clear by an example. The movement of a train from track circuit section B upon to single track block E if we consider single track block C a continuation f single track block E, would cause control relay 59 to become denergized, and allow armature 411 to fall to the lower position. At the same time the denergization of relay 59 will open armature 214, put signal 15 to danger and open circuit controller 39. Thus the multiple branches through armature 411 and circuit controller 39 .will both be broken. thereby breaking a circuit through pole changing relay 86 identical with that which includes pole changing relay 88 hereinbefore described, thus causing armatures 412 and 413 to drop and reverse the polarity of current flowing through control relay 63, which is included in a circuit in which current normally flows as follows: positive terminal of battery 369, ,Wires 414 and 415, armature 412, wires 416 and 417, armature 350, wire 418, armature 362, wire 'tarily and 419, control relay 63, wires 420, 286, 253, 252, 421, 422 and 423, armature 413, and Wires 424 and 425 to the negative terminal of the battery 369. The reversal of current through control relay 63, is preceded by a cessation of current due to the fact that an appreciable length of time intervenes between the time when armatures 412 and 413 are making contact on their front contacts and the time when they make contact ,with their back contacts; furthermore, a certain time is consumed in reversing the polarity of the core of control relay 63 so that armature 354 drops and remains out of contact with wire 426 for an appreciable length of time, consequently, the circuit for control relay 65 is bro-ken for an appreciable length of time so that armature 358 drops and remains dropped for an appreciable length of time, causing control relay 67 to become deenergized, allowing its armature 399 to drop and armature 399 dropping would, if'conducting circuit controller arm 49 were not used, break the circuit heretofore traced for pole changin relay 88 so that the same operations won (1 take place with control relay 71, that took place with control relays 63, 65 and 67, but, by using circuit controller arm 49, a shunt is formed around relay armature 399, controlled by control relay 67, so that the current which normally flows from battery 114 through pole changing relay 88 by means of wires 369, 370 and'371, arm 3720f pole changing switch 11 in the fullline position, wires 373, 374, 375, 376 and 400, armature 399, and Wire 401 to wire 402 and thence to pole changing relay 88 could flow by the multiple path from .wire 400 through wire 428, metallic are 398, conductin controller arm 49, and wire 429 to wire 4 and thence to pole changing relay 88-. It is true that the same momentary deenergization f the control relay 67 which permits the a ature 399 to drop momentarily will also drop the armature 359 momenpermit the signal 11 to start to drop from ts clear to its danger pos tion. The eehtroller ann 49 moves with the signal 11 but this movement, on account of the inertia of the signal 11, does not proceed far enough to break contact at 49 during the short momentary deenergization of the control relay 67 so that the circuit throu h the relay 88 is not interrupted. By emp oying the circuit controller arm similar to 49, on" the signals as shown, a train entering u on one certain single track block .will not e ect opposing signals farther ahead than the starting opposing signal to the single track bloc -;beyond the .'one which it is entering. Ap licant has not shownconducting contro ling arm similar toj49 upon all of the signals as it is considered perfectly obvious to one skilledintthe art that such construction may be employed if it is desired to further limit the extent of influence on opposing signals exerted by a train entering a single track block.

As hereinbefore explained, the entrance of a train onto the first track circuit section as D -of a single track block immediately sets all opposing signals governing movements over that single track block at the stop position, therefore, it will be seen, that a train having once entered a block revents an opposing train from entering t 6 same block, consequently, if a train is standing upon track circuit section A and moves onto track circuit section D before any opposing train moves from track circuit section 13 onto track circuit section D, it efiectually prevents such sec nd train from moving from track circuit section B onto track circuit section D". It is to be observed, however, that as the train progresses through the block, it clears the signals behind it successively in exactly the same manner as does a train when progressing in the direction of traflic-upon a track-way, the movement of trains over which is governed by automatic signals, in other words, as soon as a train moving in one direction has secured possession of a single track block, that block and thesignal governing movements of trains in the direction in which the assumed train is movi is for all practical purposes a section 0 double track railway as far as following trains are concerned, so that after one train has entered the single track block a following train approaching the single track block moving in the same direction as the train which precedes it, can move upon the single track block as soon as the entrance signal thereto moves to the caution position and it can do this with full assurance that it will meet no trainin the single track block traveling in a direction opposite to that which it is moving, furthermore, even should the first train proceed out of the single track block the second train which is already in the block would act upon the signaling ap paratus, exactly as dld the first train and would maintain the opposing signals at danger just as did the first train so that no train moving1 in an opposite direction could enter upon t e single track block.

In case a train moved onto a single track a block and passed one of the intermediate signals, it could then backout of the block with perfect safety, if its movement was governed *by the position of the opposing signal, that is, in backing out of the block, its movements should be controlled by those signals on the opposite side of the track from those which gave it its right to enter Y into the block; for example: if a train should move from track circuit section A, through track circuit section D and D and D onto track circuit section D 'and it was then found that. the train should return to track to the clear position as soon as such a train as we have considered, movedfrom track circuit section A over track circuit section D and D entirely upon track circuit section D consequently, if no following train had entered upon track circuit section 1), signal 13 would at least be in the caution position (as foreXample if a following train were in block C) and if no train were closer to signal 13 than the eastbound entrance to the single track block C, then signal 13 would be in the proceed position, consequently, the train could continue its backward movement toward siding A and it would furthermore be protected in its backward movement by signal 3 in the danger osition, because as soon as the train in its ackward movement passedupon the rails of track circuit section D it would deenergize track relay 27, thereby allowing armature 274 to fall and consequently, breaking the circuit of control relay 62, thereby deenergizing control relay 62 and thus allowing armature 271 to fall to its lower position interrupting the flow of current from battery 109 to both of the control wires for signal 3. The signal 3 would remain in the 40,

danger position during the time the train was upon track circuit section D and as soon as the train passed upon the rails of track circuit section B, the track relay 26 would be deiinergized and the circuit for control relay 62 would be broken at arm 270. If it was desired to continue the backward movement, it would be governed by signal 14 which would be eitherin a caution, proceed or dainger position according to the position or presence of a train upon some part of the track-way between signal 14 and the entrance signals to single track block 0 at the passing siding next inthe rear of passing siding A. r a

It should also be. noted that the train just considered which backed from track circuitsection D to track circuit section D would,'as soon as it passed entirely off from track circuit section D in its backward movement, establish a direction of movement for following trains, that is to say, the train by such movement would cause the signals to show such aspects as they would have shown if the train considered had moved from track circuitsection B. through to the fact that signal 13 is in the danger position, wires 434, 284, 283, 435, 436 and 437, control relay 65, wire 438, armature 365. wires 439and 440, armature 363, wire 441,

armature 364, in the lower position because stick relay ,78 is dene'rgized on account of control relay 64 being energized and armature 276 in the upper position, wires 442 and 443, armature 444, which is in the upper position because stick relay 77 was preliminarily energized and maintained energized by the passage of a train past signal 13 in the direction of movement governed by sigiial' 13, wires 445, 446 and 447, arm of pole changing switch 448 in the dotted line position and wires 449 and 450, to the negative terminal of the battery 110. The current flowing in the above traced path to the control relay, 65 would not be in the normal direction so armature 97 would be moved to the left but armature 355 would be in the upper position thereby allowing current to flow from battery 112 to the caution control wire 356 of signal 12 which would thereby be placed in the caution position, the signal 11, would also move to the proceed position due to the fact that control relay 65 is energized and armature 358 moved to the upper position, thereby completing a circuit in which current flows as follows: positive terminal of battery 112, wires 451, 452 and 453, arm 454 of pole changing switcl112 in the full line position as signal 12 is in the caution position, wires 455, 456 and 457 armature 358, wires 458 and 459, armature 367, wire 460, armature 366, wire 461, armature 368, wire 462, control relay 67, wires 463, 464, 465, 466 and 467, arm 468 of pole changing switch 12 in the full line position and wires 469 and 470 to the negative terminal of the battery 112. Current flowing in the above traced path and energizing con trol relay 67 would cause armature 99 to be moved to the right and armature 359 to be raised, thereby allowing current to flow from battery 114 to both the caution and proceed control wires 360 and 361, thereby causing signal 11 to move to the proceed position.

If it was desired to again change the direction of movement of the train which has heretofore been considered as backing from track circuit section D to track circuit section D after reaching track circuit section I) and again move in a same direction as when entering the block. it of course could proceed over track circuit section D as far as signal and it would find signal 4 in the full clear position if no train had in the meantime entered the single track block D from the track circuit section B. llpon ac cepting the indication given by signal 4 and passing signal 4, all of the signals, relays and armatures would again assume the position which they formerly had when the train formerly passed from track circuit section D onto track circuit section D.

It will thus be seen that a train once having gained control of a block may move with perfect safety ineither direction upon that block just so long as it moves according to the indication given by the signals, because if another train enters the single track block while the first train is in the single track block, then the second train will maintain danger signals ahead of it just exactly as does the first train, and although the first train may reverse its movement it cannot change the danger signals protecting the following train as long as the following train is upon the sections protected by the signals governing movements in a direction opposite to that in which the second train is moving.

As has hereinbefore been explained, if a train is upon any part of single track block D movincr in aneasterly direction the signal 9 will be in a, caution position. Such an indication is employed so that any train moving in a westerly direction and passlng signal 9, will never be deceived as to the position in which the signal 10 will be found on arriving thereat. If such indication were not given, but instead a proceed aspect were given at signal 9, until signal 10 moved to the danger position, then it might be very possible that a train moving in a westerly-direction could pass signal 9 in the pro ceed position and then find signal 10 in the danger position, which would necessitate a sgvere application of the brakes because at the time the train passed signal 9, .a train moving in an easterly direction might be present upon the rails of track circuit section D and might immediately thereafter move u on the rails of track circuit section D, which would as hereinbefore explained, immediately cause the signal 10 to move to the danger position, and if the train which is moving in. an easterly direction is progress in at a very high rate of s eed it might wel reach the extreme end 0 track circuit section B before the west bound train re.- ceived the indication of signal 10, and the west bound train having received a proceed aspect. at signal 9 would be running at such a speed as it would run if it had two full blocks-clear ahead of it, consequently, it might be running at such a speed that even if the indication of signal 10 in the danger position were observed at the earliest pos sible moment, it would be impossible to apply the brakes with sufficient force to bring the west bound train to a stop in the available distance so that it would crash into the east bound train standing on the rails of track circuit section B By causing signal 9 to have the caution position as soon as an east bound train enters upon single track block D, the possibility of such an accident is obviated for, under such conditions the west bound train would always receive a caution indication upon passing signal 9, and therefore, the west bound train would immediately be brought under control so it could be stopped at signal 10 without overrunning it.

It will be seen from the drawings that the system of circuits for the control. of signals for eastbound traffic interlocked with the system westbound in that each stick relay (as 74) that functions for traffic one way (east) has an armature (228) in the line control circuit (for control rcla '59) that governs a signal (1'5) for traflib the other way (wwt). Among the advantages of this reciprocal check arethat if a stick relay armature should stick after dee'nergization of the relay the signal to the rear would remain as if the train were standing where this stick occurred, so that the defect is on the side of safety.

Although I have particularly described the construction of one physical embodiment of my invention, and explained the operation and principle thereof, nevertheless, I desire to have it understood that the form selected is merely illustrative, but does not exhaust the possible physical embodiments of the idea of means underlying my invention.

What 1 claim as new and desire to secure by Letters Patent of the United States, is:

1. In a railway signal system: a trackway over which trains may move in both directions; insulating joints placed in the trackwa at intervals forming sections; a translating device controlled by each section; signals governing the movement of trains over said trackway in one direction; two signaling circuits for each signal; means controlled by all the translating devices controlled by a plurality of sections the entrance to which is controlled by separate signals for non mally closing one of said circuits for a certain signal means controlled by the entrance of a train when moving in the direction the signals govern into the track circuit section,

a the entrance to which is governed by a sig- 2. In a railway signal system: a trackway circuits for each signal; one of the said sig nal circuits governed by the translating devices of the track sections between it and the next signal in the direction the signals govern and the signalin circuits of said next signal in advance; a normally deener- 'zed device; an energizing circuit for said evice closed by the passage of a train in the direction the signals govern ast said next signal in advance;' a holding circuit for said device formed b the closing of the energizing circuit an the presence of a train on a track circuit section which the signal in advance governs the other signaling circuit governed by said normally deenergized device, and by the translatingdevices governed by the track circuit sections whichthe signal in the rear of said signal in advance governs, I

3. In a railway signalin system, in combinationra stretch of sing e track; a signal for governing trafiic over a predetermined portion of said stretch; a signal circuit for said signal; a circuit controller responsive to the' presence of a train in said predetermined portion of the stretch and open when that portion is occupied; a normally open shunt circuit for said circuit controller; means controlled by said signal' circuit for closing said shunt circuit when a train travels in the direction of traflic overned by said signal and for holding said shunt circuit closed until said predetermined portion' of the stretch is not occupied, said means preventing the closing of said shunt circuit when a train travels in the opposite direction; and means for signaling controlled jointly by said circuit controller and by said shunt circuit.

4. In railway signaling, a stretch of single track, signals located at intervals for overning traffic in one direction through t e stretch and other signals located at intervals for governing traflic in the other direction through the stretch, a signal relay for the control of each signal, a cirtrack, over which traflic movesf in both d1- rections, signals located at intervals for governing traflic in one direction through said stretch, a signal relay for the control of each signal, a circuit for each relay each of which circuits includes a contact of the relay for the signal next in advance, track circuits for the stretch including track relays for controlling said signal relay circuits, a branch for each signal relay circuit around the signal relay contact which controls such circuit, and means for controlling each of said branches.

6. In railway signaling, a stretch of single track, signals located at intervals for governing trailic in one direction through the stretch and other signals located at insaid signal relay inefi'ective to control the signal relay for the next signal in the rear governing trailic in the same direction.

7. In railway signaling, a stretch of single track, signals located at intervals for governing traflic in one direction through the stretch and other signals located at intervals for governing traffic in the other direction through the stretch, a signal relay for the control of each signal, a circuit for each signal relay each of which circuits includes a contact of the signal relay for the next signal in advance overning traiiic in the same direction, trail relays connected with the stretch for controlling the circuits ofthe signal relays, a branch for each signal relay circuit around the contact of the signal relay which controls such circuit, and means for controlling each of said branches.

8. In railway signaling, a stretch of single track, signals located at intervals for governing traflic in one direction through the stretch and other signals located at intervals for governing traffic in'the other direction through the stretch, a signal relay for the control of each signal, a circuit for each signal relay each of which circuits includes a contact of the signal relay for the next signal in advance governing traific in the same direction, track relays connected with the stretch for controlling the circuits of the signal relays, a branch for each signal relay circuit around the contact of the signal relay which controls such circuit, auxiliary relays for the control of said branches, and circuits for the auxiliary relays controlled by the signal relays.

9. In combination, a stretch of single track, signals located at intervals for governing trafiic in one direction through the 

